JPH0212109B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an artificial dialysis apparatus that can accurately control ultra-overpressure without being affected by offset fluctuations.

<Conventional technology> Conventionally, in an artificial dialysis machine, a signal (blood pressure M 1 ) from a blood pressure sensor installed in the blood circuit of a dialyzer and a signal (dialysate pressure M ₁ ) from a dialysate pressure sensor installed in the dialysate circuit are used. ₂ ), and controls an auto-cleaner installed in the blood circuit so that the difference between the blood pressure _M1 and the dialysate pressure _M2 matches the set limit overpressure.

In the above configuration, since there is a pressure drop in the blood circuit and dialysate circuit of the dialyzer, the extreme overpressure (TMP) does not match M ₁ - _{M 2} and becomes as follows, TMP = M ₁ - M ₂ +△P (However, △P: Offset due to pressure loss, etc.) The characteristics of the ultraviolet rate (UFR) are shown in Figure 1.

It has been confirmed through experiments that the offset ΔP changes depending on blood viscosity, blood flow rate, dialysate flow rate, etc., and it changes when these changes. In conventional artificial dialysis machines, it is difficult to accurately determine the offset ΔP, so a fixed value is determined empirically. Therefore, the UFR as set
It was difficult to obtain.

<Problems to be Solved by the Invention> A technical problem to be solved by the present invention is to realize an artificial dialysis apparatus that can accurately control TMP without being affected by the offset.

There is a particular thing.

<Means for Solving the Problems> The configuration of the present invention is to connect a blood circuit for blood supply and a blood circuit for blood reflux between the blood side of a dialyzer and a patient, and to connect blood to the blood supply circuit. A pump is provided, a dialysate circuit for supplying dialysate and a dialysate circuit for discharging dialysate are connected to the dialysate side of the dialyzer, a blood pressure sensor is provided in the blood circuit, and a dialysate circuit is connected to the dialysate side of the dialyzer. A pressure sensor is provided, and an ultra-overpressure control means is provided for controlling ultra-overpressure between the blood circuit and the dialysate circuit, and during dialysis, blood and dialysate are supplied to the blood side and dialysate side of the dialyzer, respectively. and controlling the extreme overpressure control means such that the difference between the blood pressure detected by the blood pressure sensor and the dialysate pressure detected by the dialysate pressure sensor matches the set extreme overpressure. The dialysis device includes the following components A to E.

A Bypass line B connected between the supply dialysate circuit and the discharge dialysate circuit B A solenoid valve provided in the discharge dialysate circuit upstream of this bypass line and closed during dialysis C. A circuit switching means provided between the dialysate supply circuit and the bypass line, which switches the flow of the dialysate to the dialyzer side during dialysis and to the bypass line side when measuring ultracapacity; a container whose lower part is connected to the upstream side of the electromagnetic valve and whose upper part is connected to the downstream side of the electromagnetic valve via a metering line, and which is emptied by opening the electromagnetic valve when measuring ultra-high performance; From the time T during which the electromagnetic valve is closed and the liquid is filled by the limit excess, the limit pass rate UFR is determined by the following calculation: UFR=V/T (where, V is the capacity of the container). At the time of overcapacity measurement, the circuit switching means is switched to the direction in which the dialysate flows to the bypass line side, the extreme overpressure control means is controlled based on two different set extreme overpressures, and the measurement is performed with the measuring instrument. Based on the measurement results at each set limit overpressure, a characteristic curve between the limit pass rate and limit overpressure of the dialyzer is determined, and the set limit corresponding to the limit pass rate input from the operation panel is determined during dialysis. Determine the external overpressure using the characteristic curve,
A control unit that thereby controls the ultra-overpressure control means <Function> At the time of dialysis, the setting TMP set by the control unit
The TMP of the dialyzer is controlled so as to match . When measuring ultra-high performance, the solenoid valve is opened by a control signal given from the control unit,
The scale is emptied. The solenoid valve is then closed and dialysate is drained through the bypass line. During this time, the dialyzer is set
The meter is controlled by TMP, and liquid flows into the measuring device due to ultrafiltration. of the dialyzer based on the time the meter is filled with liquid.
Find UFR. In the present invention, the UFR measurement performed in this manner is performed using two different TMP settings, and the UFR of the dialyzer is determined from the two measurement results and their corresponding TMPs.
Find the characteristic curve with TMP and memorize it.
During dialysis, when the UFR is set from the operation panel, the set TMP corresponding to the input UFR is determined using the characteristic curve. This is used to control the extreme overpressure control means.

<Example> The present invention will be described below with reference to the drawings. FIG. 2 is a block diagram of an artificial dialysis apparatus that implements the method of the present invention. The basic configuration of this device is dialyzer 1, its peripheral equipment, and the signals and signals from this peripheral equipment.
The control section 3 includes a microcomputer that receives signals from an operation panel 2 for setting the UFR, performs predetermined arithmetic processing, and controls peripheral devices. The storage section of the control section 3 stores processing routines and arithmetic programs, including a program for determining the characteristics of the dialyzer 1 by periodically switching the circuit according to the method of the present invention.

The dialysate circuit of the dialyzer 1 includes a dialysate supply pump 4 rotating at a constant speed, a solenoid valve 5 operated by a control unit 3, and a dialysate pressure sensor 6 (an output signal corresponding to the dialysis pressure _M2 is input to the control unit 3). a supply line 7 with a solenoid valve 8 operated by the control unit 3; a bypass line 11 with a solenoid valve 10 operated by the control unit 3;
and a metering line 15 with a meter 14 consisting of a container 12 and an ultrasonic level sensor 13 (the output signal of which is input to the control unit 3).

The blood circuit of the dialyzer 1 includes a blood pump 16 that rotates at a constant speed, an arterial chamber 18 (an output signal corresponding to blood pressure _M1 is input to the control unit 3),
It includes an automatic cleanser 19 operated by a control unit 3 and a venous chamber 20.

In the above configuration, during dialysis (ultrapass),
While blood from the patient is continuously flowing into the blood circuit of dialyzer 1, solenoid valve 5 is opened and solenoid valves 8 and 10 are closed to allow dialysate to flow continuously at a constant flow into the dialysate circuit of dialyzer 1. (The flow path is supply line 7→dialyzer 1→discharge line 9→meter 14→metering line 15→discharge destination). At this time, the control unit 3 controls the TMP as described below.
The auto-cleaner 19 is operated to match TMP _c1 to achieve a UFR of a predetermined value (UFRc).

Hereinafter, a method for determining the ultraviolet characteristics of the dialyzer 1, which is a characteristic part of the method of the present invention, will be explained. According to a program stored in the control unit 3, the solenoid valve 5 is periodically switched to close, and the solenoid valves 8 and 10 are switched to open. As a result, a flow path is established in which the dialysate flows from the supply source to the discharge destination via the bypass line 11 (the supply of dialysate to the dialyzer 1 is interrupted), and the meter 14 (container 12) is emptied.
Similarly, according to the program, after a predetermined period of time has elapsed, the solenoid valve 8 is closed, and a flow path from the dialyzer 1 to the discharge line 9 to the metering line 15 to the discharge destination is formed.

According to the program, a TMP _T larger than the TMP at the time of treatment stored in the control unit 3 is given (see FIG. 3), and the TMP is controlled using this value as the set TMP.

Measuring the dialysate by ultrafiltration with a meter 14,
The time T until the container 12 is full is detected by the ultrasonic level sensor 13, and the ultrasonic pass rate when TMP _T is detected.
UFR _T (point A in Figure 3) is determined from UFR _T = V/T (where V is the internal volume of the container 12).

The ultra-high performance (UFRP _T ) at this time can be found by the following calculation.

UFRP _T = (UFR _T ) / (TMP _T ) Based on this UFRP _T , calculate TMP (theoretical value) to obtain UFR _c (UFR during actual treatment, which is the value set from the operation panel 2). less than or equal to
TMP _c ) is calculated (see the following formula).

TMP _c = UFR _c / UFRP _T All of the above calculations are performed according to the above program, and after opening the solenoid valve 8 again according to this program to empty the meter, the solenoid valve 8 is closed and the dialyzer is 1→Discharge line 9→Measuring line 15→Discharge destination flow path is formed.

According to the program, TMP is controlled by setting TMP _c as TMP, and the dialysate due to the ultraviolet passage at this time is measured with the meter 14, and the ultraviolet passage rate UFR _c1 when TMP _c is set (Fig. 3). Find point B).

The characteristic C of the dialyzer 1 is determined using these UFR _T , UFR _c1 , TMP _T and TMP _c , and the characteristic curve is stored in the storage section of the control section 3 .

During dialysis, use this characteristic curve to obtain the ultra-overpressure, that is, TMP _c1 , to obtain the ultra-pass rate UFR _c set from the operation panel, and set this TMP.
The TMP of dialyzer 1 is controlled as follows.

Note that, in the present invention, the arithmetic processing for determining the characteristics of the dialyzer 1 is not limited to the above-described method. For example, as shown in Fig. 4, predetermined TMP _T1 and TMP _T2 (however, TMP _T2 < TMP _c
<TMP _T1 ) were added to the dialysis membrane of dialyzer 1 to measure UFR _T1 and UFR _T2 , and these TMP _T1 ,
The characteristic D may be determined using TMP _T2 , UFR _T1 , and UFR _T2 . In addition, as shown in Figure 5, TMP _T1 can be set in advance to dialyzer 1.
In addition to the dialysis membrane, find UFR _T1 and find the characteristic E from this. Next, TMP _T2 corresponding to UFR _c is determined based on characteristic E. Configure the TMP calculation circuit again and add TMP _T2 to the dialysis membrane of dialyzer 1.
Find UFR _T2 and use the characteristic F from this UFR _T2 and TMP _T2.
seek. Next, we will calculate TMP _T3 corresponding to UFR _c based on this characteristic F, and configure a TMP calculation circuit.
Find UFR _T3 . Below, UFR _TN (N is a positive integer)
The above calculation is repeated until the value falls within the allowable range for the setting UFR _c .

<Effects of the Invention> According to the present invention, dialyzer-specific
A characteristic curve between UFR and TMP was obtained, and during dialysis,
When the UFR is set from the operation panel, this characteristic curve is used to accurately determine the set TMP corresponding to the input UFR, and if control is performed using this, accurate TMP control can be achieved. In the apparatus according to the embodiment of the present invention, TMP is controlled by an autocleaner provided in the blood circuit, but it may be controlled by a negative pressure pump provided in the discharge line of the dialysate circuit. Further, the measuring instrument is not limited to the type used in the apparatus according to the embodiment of the present invention.

[Brief explanation of drawings]

FIG. 1 is a characteristic diagram of the dialyzer, FIG. 2 is a configuration diagram showing an embodiment of the device of the present invention, FIG. 3 is an explanatory diagram of the operation of the embodiment of the device of the present invention shown in FIG. 2, and FIGS. 4 and 5. FIG. 6 is an explanatory diagram of the operation in another embodiment of the present invention. 1: dialyzer, 2: operation panel, 3: control unit, 4: dialysate supply pump, 5, 8, 10: solenoid valve, 6: dialysate pressure sensor, 7: supply line, 9:
Discharge line, 11: Bypass line, 12: Container, 13: Ultrasonic level sensor, 14: Meter, 15: Metering line, 18: Blood pressure sensor, 1
9: Auto cleanse.

Claims (1)

[Scope of Claims] 1. A blood circuit for blood supply and a blood circuit for blood reflux are connected between the blood side of the dialyzer and the patient, a blood pump is provided in the blood supply circuit, and the dialysate of the dialyzer is A dialysate circuit for supplying dialysate and a dialysate circuit for draining dialysate are connected to the side.
A blood pressure sensor is provided in the blood circuit, a dialysate pressure sensor is provided in the dialysate circuit, and an extreme overpressure control means is provided for controlling an extreme overpressure between the blood circuit and the dialysate circuit. When blood and dialysate are passed through the blood side and dialysate side of the dialyzer, respectively, and the difference between the blood pressure detected by the blood pressure sensor and the dialysate pressure detected by the dialysate pressure sensor exceeds the set limit. An artificial dialysis device that controls the ultra-overpressure control means so as to match the pressure, and the following A to E
An artificial dialysis device characterized by having the following as a component. A: a bypass line connected between the supply dialysate circuit and the discharge dialysate circuit; B: a bypass line provided in the discharge dialysate circuit upstream of the bypass line, and closed during dialysis. a solenoid valve; and C. a circuit switching means provided in the dialysate supply circuit and the bypass line, which switches the flow of dialysate to the dialyzer side during dialysis and to the bypass line side during ultraperformance measurement. , D, a level sensor is provided, a lower part is connected to the upstream side of the solenoid valve, and an upper part is connected to the downstream side of the solenoid valve through a metering line, and the solenoid valve is opened when measuring the extreme overpower. From the time T during which the container emptied by closing the solenoid valve is filled with liquid due to the ultra-violet passage, the ultra-violet rate UFR can be calculated by the following calculation: UFR=V/T (where, V: capacity of the vessel). E. At the time of measuring the ultracapacity, the circuit switching means is switched to the direction in which the dialysate flows to the bypass line side, and the ultralimit overpressure control means is controlled based on two different types of set limit overpressures. A characteristic curve of the ultra-pass rate and ultra-overpressure of the dialyzer is determined based on the measurement results at each set ultra-overpressure measured by the measuring device, and the characteristic curve of the ultra-pass rate and ultra-overpressure of the dialyzer is determined based on the measurement results at each set ultra-overpressure, and the limit value input from the operation panel is determined during dialysis. Find the set limit overpressure corresponding to the overpass rate using the characteristic curve,
As a result, a control section that controls the extreme overpressure control means